Article
I would like to thank Ms Hughes et al for shedding light on dental manifestations associated with congenital metabolic disorder hypophosphatasia (HP)in children.1 The conclusions of the authors of this recent paper published in Dental Update are concurrent with my reflections in the review report which emphasized the need for thorough diagnosis of dental patients with unexplained premature teeth loss.2
The early loss of deciduous teeth or loss of permanent teeth support, despite good plaque control, should draw the attention of primary care dental practitioners, with the focus being on potentially inherited aetiology, including undiagnosed hypophosphatasia. As a detailed mechanism of premature tooth loss is still unknown, further studies might deliver a clearer answer. There is no doubt that metabolic disturbances during tooth structure development in early stages of odontogenesis, caused by a low level of alkaline phosphatase, affect the mineralization process of hard tissues, especially root cementum, impacting teeth support.
The results of our research, carried out with the use of SEM microscopic, photoelectron XPS spectroscopy and diffraction XRD, a study on an extracted molar tooth in an adult patient with a severe form of HP affecting skeletal system and oral health, brought interesting findings.3 Alkaline phosphatase deficiency seems to have a relatively mild influence on the dentine of third molars, with naturally prolonged development due to a late mineralization. In the case of the permanent dentition with late formation, the chemical composition may not be significantly different compared to healthy individuals. However, qualitative variations within cementum are usually eminent and obvious. According to our study, no considerable morphological changes within dentine, determined by SEM, were noticed. On the contrary, malformations of cementum suggested an impaired formation of an external layer of the root in HP (Figure 1). The disturbed homeostasis of mineral elements is poorly understood but appears to reflect their defective uptake by poorly growing hard tissues. Guidelines related to interdisciplinary dental care provided by dedicated societies could improve management of patients with HP. Any abnormal findings noticed by clinicians during routine dental screening and affecting periodontal support (Figure 2) need to be carefully validated following differential diagnosis, including the basic assessment of serum level of alkaline phosphatase. As we know, the range of HP symptoms varies significantly from a mild form with very distinctive, asymptomatic local defects, to severe systemic impairments.4 Hence, mild forms of HP may be potentially undiagnosed for the first few years of a patient's life. Close co-operation with the general dental practitioner, specialist orthodontist, genetics specialist and other medical professionals would be vitally important, particularly for young patients with HP, in order to secure the patient's health status and wellbeing.
